Process for the preparation of α-[4-(4-chlorobenzoylaminoethyl)-phenoxy]-isobutyric acid

Abstract

A process for the preparation of 2-[4-(4-chlorobenzoylaminoethyl)-phenoxy]-2-methylpropionic acid of the formula ##STR1## which process comprises reacting N-(4-chlorobenzoyl)-tyramine with acetone and chloroform in a mole ratio of 1:20-100:2-10, in the presence of 3 to 4 moles of alkali per mole of chloroform, at a temperature of from about 10° to 40° C.

What is claimed is: 
     
       1. In a process for the preparation of 2-[4-(4-chlorobenzoylaminoethyl)-phenoxy]-2-methylpropionic acid of the formula ##STR3## comprising reacting N-(4-chlorobenzoyl)-tyramine with acetone and chloroform, the improvement consisting of carrying out the reaction at a temperature of from about 20° to 40° C. in a mole ratio of 1:20-100:2-10 (tyramine:acetone:chloroform), and in the presence of 3 to 4 moles of alkali per mole of chloroform. 
     
     
       2. Improvement as claimed in claim 1 wherein the reaction product obtained is neutralized with a non-toxic organic or inorganic base to produce a salt of said 2-[4-(4-chlorobenzoylaminoethyl)-phenoxy]-2-methylpropionic acid. 
     
     
       3. Improvement as claimed in claim 1 wherein 3 to 6 moles of chloroform are used per 1 mole of N-(4-chlorobenzoyl)-tyramine. 
     
     
       4. Improvement as claimed in claim 1 wherein 3.2 to 3.5 moles of alkali are used per mole of chloroform. 
     
     
       5. Improvement as claimed in claim 1 wherein the reaction is carried out at a temperature of 15° to 30° C. 
     
     
       6. Improvement as claimed in claim 5 wherein the reaction is carried out at a temperature of 20° to 25° C.